Vehicle transmission and hybrid drivetrain

Abstract

A motor vehicle transmission including an interface to a drive unit, a drive shaft, an output shaft coaxial to the drive shaft, a differential transmission paraxial to the drive shaft, a device for forming gear ratios between the drive and output shafts, and an electric motor with a fixed stator and a rotatable rotor. The output shaft is connected with the differential transmission by a chain drive and a downstream gear set coaxial to the differential transmission. The electric motor is at an axial end of the transmission where the interface to the drive unit is formed. The rotor is connected with the drive shaft. The chain drive is axially between the differential transmission and the downstream gear set or the downstream gear set is axially between the chain drive and the differential transmission, and the chain drive is axially between the electric motor and the downstream gear set.

The invention claimed is: 
     
       1. A transmission (G) for a motor vehicle, the transmission (G) comprising:
 an interface (G 1 ) to a transmission-external drive unit (VM); 
 a drive shaft (GW 1 ); 
 an output shaft (GW 2 ) coaxial to the drive shaft (GW 1 ); 
 a differential transmission (AG) paraxial to the drive shaft (GW 1 ); 
 a device for forming various gear ratios between the drive shaft (GW 1 ) and the output shaft (GW 2 ); and 
 an electric motor (EM) with a rotationally fixed stator (S) and a rotatable rotor (R), 
 wherein the output shaft (GW 2 ) is in constant operative connection with the differential transmission (AG) by a chain drive (K) and a downstream gear set (P) coaxial to the differential transmission (AG), 
 wherein the electric motor (EM) is at an axial end of the transmission (G) at which the interface (G 1 ) to the transmission-external drive unit (VM) is formed, 
 wherein the rotor (R) is in constant operative connection with the drive shaft (GW 1 ), and 
 wherein the chain drive (K) is axially between the differential transmission (AG) and the downstream gear set (P). 
 
     
     
       2. The transmission (G) of  claim 1 , wherein the differential transmission (AG) is arranged at an end of the transmission (G) at which the interface (G 1 ) to the transmission-external drive unit (VM) formed. 
     
     
       3. The transmission (G) of  claim 1 , wherein the downstream gear set (P) is axially between the electric motor (EM) and the chain drive (K). 
     
     
       4. The transmission (G) of  claim 1 , wherein the downstream gear set (P) is a negative planetary gear set having a ring gear (E 3 ) permanently fixed in a rotationally fixed manner, a sun gear (E 1 ) permanently connected to a chain gear (K 2 ) of the chain drive (K) that is coaxial to the differential transmission (AG), and a planet carrier (E 2 ) permanently connected to the differential transmission (AG). 
     
     
       5. The transmission (G) of  claim 4 , wherein the device for forming the various gear ratios between the drive shaft (GW 1 ) and the output shaft (GW 2 ) comprises a plurality of planetary gear sets (P 1 , P 2 , P 3 ) and a plurality of shift elements (A, B, C, D, E), wherein one of the plurality of shift elements (E) is at least partially radially inside a chain gear (K 1 ) of the chain drive (K) that is coaxial to the drive shaft (GW 1 ). 
     
     
       6. The transmission (G) of  claim 1 , wherein the electric motor (EM) is coaxial to the drive shaft (GW 1 ). 
     
     
       7. The transmission (G) of  claim 1 , wherein the electric motor (EM) is paraxial to the drive shaft (GW 1 ). 
     
     
       8. The transmission (G) of  claim 1 , wherein an axial distance between the chain drive (K) and the interface (G 1 ) is greater than an axial distance between the electric motor (EM) and the interface (G 1 ). 
     
     
       9. A hybrid drive train for a motor vehicle with the transmission (G) of  claim 1 . 
     
     
       10. A transmission (G) for a motor vehicle, wherein the transmission (G) comprises:
 an interface (G 1 ) to a transmission-external drive unit (VM); 
 a drive shaft (GW 1 ); 
 an output shaft (GW 2 ) coaxial to the drive shaft (GW 1 ); 
 a differential transmission (AG) paraxial to the drive shaft (GW 1 ); 
 a device for forming various gear ratios between the drive shaft (GW 1 ) and the output shaft (GW 2 ); and 
 an electric motor (EM) with a rotationally fixed stator (S) and a rotatable rotor (R), 
 wherein the output shaft (GW 2 ) is in constant operative connection with the differential transmission (AG) by a chain drive (K) and a downstream gear set (P) coaxial to the differential transmission (AG), 
 wherein the electric motor (EM) is at an axial end of the transmission (G) at which the interface (G 1 ) to the transmission-external drive unit (VM) is formed, 
 wherein the rotor (R) is in constant operative connection with the drive shaft (GW 1 ), and 
 wherein the downstream gear set (P) is axially between the chain drive (K) and the differential transmission (AG), and the chain drive (K) is axially between the electric motor (EM) and the downstream gear set (P). 
 
     
     
       11. The transmission (G) of  claim 10 , wherein the downstream gear set (P) is a negative planetary gear set having a ring gear (E 3 ) permanently fixed in a rotationally fixed manner, a sun gear (E 1 ) permanently connected to a chain gear (K 2 ) of the chain drive (K) that is coaxial to the differential transmission (AG), and a planet carrier (E 2 ) permanently connected to the differential transmission (AG). 
     
     
       12. The transmission (G) of  claim 11 , wherein the device for forming the various gear ratios between the drive shaft (GW 1 ) and the output shaft (GW 2 ) comprises a plurality of planetary gear sets (P 1 , P 2 , P 3 ) as well as a plurality of shift elements (A, B, C, D, E), wherein one of the plurality of shift elements (E) is at least partially radially inside a chain gear (K 1 ) of the chain drive (K) that is coaxial to the drive shaft (GW 1 ). 
     
     
       13. The transmission (G) of  claim 10 , wherein the electric motor (EM) is coaxial to the drive shaft (GW 1 ). 
     
     
       14. The transmission (G) of  claim 10 , wherein the electric motor (EM) is paraxial to the drive shaft (GW 1 ). 
     
     
       15. The transmission (G) of  claim 10 , wherein an axial distance between the chain drive (K) and the interface (G 1 ) is greater than an axial distance between the electric motor (EM) and the interface (G 1 ). 
     
     
       16. A hybrid drive train for a motor vehicle with the transmission (G) of  claim 10 .